First download release of openSeaChest
Open a CMD as administrator
Enter inside folder where you will find
Execute below command to find your driver serial number
openSeaChest_Basics.exe openSeaChest_Firmware --scan
Then type seagate firmware download to google
Enter your serial number to the Firmware Downloads and search your firmware
Then download latest firmware
Then extract it into openSeaChest folder
I also renamed for easy call from CLI
Then look PID of your disk that you want to update
Then modify this command according to you and execute it. It will update the firmware. Remember this can cause data loss so always backup files and later verify them. I have a byte comparison file verification software that I have coded. I am using it to verify.
openSeaChest_Basics.exe SeaChest_Firmware -d PD1 --downloadFW SN04.lod
After this turn off your computer. Not just restart. Wait 15 seconds and turn on again. Now when you scan disks you should see new firmware.
As in my case you see one of the drive is SN04 and the other one is SN03.
Hopefully I will record a video tutorial to upgrade SN03 one.